Double-acting pneumatically operated door opener



April 27, 1954 R. 1. MEYERHOLZ 2,676,796

DOUBLE-ACTING PNEUMATIC/ALLY OPERATED DOOR OPENER Filed June 5, 1950 2 Sheets-Sheet 2 INVENTOR.

' J 9 RHE/N/ER MEYERHOLZI BY 7W1 MM, 7%

ATTORNEYS Patented Apr. 27, 1954 UNITED STATES PATENT OFFICE DOUBLE-ACTIN G PNEUMATICALLY OPERATED DOOR OPENER Rheinier I. Meyerholz, Cupertino, Calif. Application June 5, 1950, Serial N 0. 166,201 8 Claims. (01. 268--66) This invention relates to new and useful improvements in double-acting pneumatically-operatcd door opener. More particularly the invention relates to a means for opening a swinging door in either direction by pneumatic means set in motion manually by actuation of a switch on the door.

The present invention is intended for use in conjunction with swinging doors having doubleacting, floor door checks, such as are in common use at the present time. The invention constitutes an improvement whereby said doors are pneumatically actuated to open in either direction. Pneumatic pistons are connected to the door by mechanical means and said pistons are actuated by solenoids which are energized upon closing of switches associated with the door in such manner that when the door is touched from either side a switch is closed which energizes the proper solenoid to open the door in the direction opposite the side on which the door is touched.

Further provision is made so that if two persons touch the door from opposite sides simultaneously or within a short time of each other, the door is not automatically operated, but rather comes to equilibrium and must be manually moved to open position in order to reset the electrical circuits which operate the door controlling means.

Thus the instant invention provides automatic door opening means for swinging doors operable to open the door in either direction merely upon the touching of a portion of the door which closes a switch, which in turn establishes an electric circuit controlling the operation of the door. The mechanism is simple and relatively inexpensive and aifords obvious advantages over such automatic door-opening means as photo-electric cells which are presently used.

Further objects of the present invention will become apparent upon referring to the accompanying specification and drawings in which similar characters of reference represent corresponding parts in the several figures of the drawings.

Referring to the drawings:

Fig. 1 is a fragmentary elevation, partially in section, showing a portion of the door and actuating mechanism.

Fig. 2 is a horizontal section taken substantially along the line 22 of Fig. 1.

Fig. 3 is a horizontal section taken substantially along the line 33 of Fig. 1.

Fig. 4 is a schematic view of the invention showing a wiring diagram and associated mechanical means.

' at the present time for Fig. 5 is a vertical section through one of the pneumatic cylinders.

Fig. 6 is a vertical section through a pneumatic valve controlling said pneumatic cylinders.

Fig. 7 is a fragmentary view of a glass door in connection with which the invention may be employed and showing the horizontal rails or pushbars hinged to said door which operate the switches controlling operation of the door-opening mechanism.

Fig. 8 is a vertical section taken substantially along the line 8-8 of Fig. 7.

Fig. 9 is a wiring diagram of a modification of the invention.

As shown in Fig. l, the instant invention is used to actuate a door 28, said door being hung to swing about .a vertical axis adjacent one side edge thereof. Vertical pintles 2i and 22 are fixed to the door at the top and bottom thereof, said pintles extending vertically upward and downward from the door respectively. It is customary doors of the general type with which the present invention is connected to employ double-acting door check mechanism 23 which is associated with lower pintle 22, and located in a box 24 below the level of the floor immediately beneath the door. Horizontal link 26 is fixed at about its midpoint adjacent the top of box 24 to p-intle 22. To each end of said link 26 is pivotally connected 2. spring linkage 27, one of said linkages being connected to helical spring 28 and the other said linkage 21 being connected to helical spring 29. Said helical springs 28 and 29 have their axes vertically disposed and the linkage is such that when the door 25 is pushed open in either direction said springs are biased in such manner that they tend to restore the door to closed position. In order to prevent the door from slamming and possibly striking the person opening the door, two check cylinders 3| are provided, said cylinders containing horizon tally slidable pistons 32, the rods 33 of which are pivotally connected to opposite ends of horizontal link 34 which is also fixed at its midpoint to pintle 22 in such manner that as the door swings, one piston 32 is moved inwardly of its cylinder 3. and the other piston is moved outwardly of its cylinder. The pistons 32 are so arranged, as well understood in this art, as to cheek closing movement of the door 26 and thus retard the closing action of springs 28 and 29. All of the foregoing mechanism is used in connection with the present invention, but is of conventional design. Although a preferred form of door check has been illustrated and described, it will be understood that the instant invention may be used in conjunction with other types of door checks, and that the details of the door check constitute no part of the instant invention.

Pintle 22 is elongated and received. at its lower end in a bearing M affixed to a stationary part of the building. The lower end of the pintle carries gear ir. which rotates with pintle 22. The instant invention causes rotation of said gear and said pintle 22 and thereby opens and closes door 2%. Said gear l; is rotated by means of two horizontally reciprocating racks 43 which move in opposite directions, the teeth of said racks engaging the teeth or" said gear 42. When the door is in closed position, each of said racks :ltl is approximately at its mid-position. When the mechanism is actuated to open the door in one direction, one of said racks 43 is projectedand the other retracted.

positely moved. Each of said racks d3 carries at one end a, rod and each of said rods is received in an individual pneumatic cylinder 15 or it shown in detail in Fig. 5, the ends of said rods remote from said racks 43 being directly connected to pistons ll slidable within either said cylinder 45 or at. Packing gland 68 is disposed at one end of each said cylinder 55 or at to seal the opening through which rod 4 reciprocates. in order to provide an air-tight seal between said piston i! and the inner walls or" said cylinder ie or at, the piston is formed with a round plate is through which the end of rod i i extends and on opposite sides of said plate 49 are cup-shaped packing members the upturned flanges of the cupshaped members being directed away from said plate d9. Thus, by means of a nut 52 disposed on the threaded portion 53 of said rod i t and bearing against right-hand cup 5!, as viewed in Fig. 5, and nut 54 on the threaded extremity of rod e l bearing against left-hand cup, the cups 5% may be tightened and held in position. It will be observed that there is a port 55 at each end of said cylinder 65 or at through which compressed air may enter in order to drive piston 47 toward either end, and during such movement port 56 at the opposite end is arranged to discharge to the atmosphere. As has been stated, there are two such cylinders and 46, one associated with each of said racks 43.

Compression and exhaust through the left and right-hand ports of each of said cylinders 45 and it is controlled by means of two air valves es and El shown in detail in Fig. 6, valve 853 being connected by means of piping 62 to the righthand-end port 55 of first cylinder 45 and to the left-hand-end port 58 of second cylinder d5. Valve 6! is connected to the lefthand-end port 56 of said first cylinder and the right-hand-end port 56 of second cylinder 46 by piping 63-. Thus, as will be seen particularly with reference to l, valve 6%} when in open position causes compression at the right-hand end of cylinder 5 and the left-hand end of cylinder 65 which causes one rack 43 to retract and the other rack 53 to project, thereby twisting pintle 22 as viewed from above in Fig. 4 in a counterclockwise direction. The other valve 58, when in open position, results in pintle 22 being twisted in a clockwise direction. It will be seen that valve 61! (or ii 5) comprises a hollow tube 86 with a dividing wall 6'. sealing of? said tube. On either side or" said wall 61 is a row of perforations 53. The outer surface of said tube SE is smooth and slidable thereupon is a cylindrical collar or W hen it is desired to open the door in the opposite direction racks 13 are opsleeve member 59, the v inner surfaces of said sleeve 69 being provided with rubber gaskets H which seal against the outer surface of tube BE. Compressed air from a suitable source is introduced into the sleeve member ts through the left-hand end as viewed in Fig. 6. Because passage of said air through the tube is blocked by partition 6?, the air passes out through left-hand perforations 68 into the hollow cylinder provided by the sleeve 89 which encompasses tube ESE. When the sleeve 69: is in lefthand position as shown in full lines in Fig. 6, further passage of the air is blocked, and it will be seen that the other end of tube 56 (i. e., the righthand end as viewed in Fig. 6) is open to the atmosphere by reason of right-hand perforation 68 communicating with the atmosphere. When sleeve 8% is moved to the right, i. e., to the dottedline position as shown in Fig. 6, air entering through the left-hand end of the tube 66 passes through the left-hand perforations $8 into sleeve 59 and thence through right-hand perforations 68 into the right-hand end of the tube 66 which communicates with ports 56 of pneumatic cylinders 45 and as.

Movement of sleeves til on valves cc and 61 is controlled by solenoids it and 'i'i respectively (see Fig. 4), which are directly connected to said sleeves $9 by of rigid rods l8 which are attached to the cores of said solenoids. Energizetion of solenoid causes rod E8 to move sleeve 69 of valve 6?] to the right and thereby apply COlllpressed air to the right end of cylinder is and left end of cylinder thereby moving upper rack *5 to the left and twisting pintle 22 counter-clockwise, as viewed in Fig. 4. In order to prevent overheating of said solenoids "iii and Ti bimetallic switches 82 are attached thereto and upon overheating of said switche iii the relay circuits hereinaiter described will be broken until the solenoids have cooled.

Actuation of solenoids "l6 and I1 is controlled by circuits energized upon closing of microswitches 86 and t located on the door 23 which are manually opened and closed. In the preferred embodiment of my invention, I employ the customary horizontal hand rails 88 or push bars which are frequently placed on doors in public buildings to actuate switches i6 and H. As seen particularly in Figs. 7 and 8, three horizontal push bars 88 are provided which extend the full width of the door panel. The three bars 88 are connected to vertical members 89 which are pivotally connected at their lower ends to door 25} by hinges 95. A spring $32 is interposed which urges said bars 88 away from the central glass door panel 83 and a stop 9 restrains outward movement of bars 88 from the position shown in Fig. 8. Micro switch 85 is embedded on one side of door panel and switch d! on the other side of said door. Thus when the right-hand bars 88 as viewed in Fig. 8 are touched, bars 38 are moved inwardly about the pivot oi hinge 9! thereby closing switch $36. Switch c"! is provided at the other end of bars 38 in contact with left-hand bars 88 and when said left-hand bars 813 are touched, said second switch 8? i closed. Thus, a person approaching door it] from either direction, upon touching rails 88 causes one or the other of said switches 85 and 8'! to be closed, depending upon the side of the door from which the approach is made. As will hereinafter appear, if persons approach door 20 from opposite sides and touch rails 88 on opposite sides of the door at about the same time, the mechanism is brought into equilibrium and the door 20 must be manually opened in order to reset the relays which actuate the door.

5 The electrical circuits and pneumatic circuits are illustrated in Fig. A source of electric current is provided which energize the solenoids 16 and 11, preferably such source being 115 volts. Said source is carried through primary coils of transformer it: which reduces the secondary side voltage to about 24 volts which reduced voltage is used for the relay circuits. As has been stated, thermal switches 8! are provided on solenoids 16 and 11. Assuming that said switches are closed, i. e., that the solenoids have not overheated, a ground connection is established between one contact of each of said switches 53$ and 81, it being understood that both primary and secondary circuits of transformer HiI are grounded. Closing of switch 8G by manual contact completes the circuit to the other secondary pole Hit? of transformer WI through coil I 512 of relay Hi3 and throws relay [123, as viewed in Fig. 4, to the right. This causes contacts I65 to close, and thus a circuit is completed from primary pole l 91 of transformer HM to solefnoid 11 and thence to ground. This causes valve 6| to be actuated, which results in door 20 being opened in a direction. opposite that from which it has been touched. A holding circuit is also closed by reason of the closing of contacts I55, one con- 'tact Ills being connected to secondary pole I85 of transformer Iti and the other contact 2% being connected to sliding contact lilo which engages a 'metallic segment I 339 on the upper surface of gear ,42, said metallic segment 169 being grounded as .will beseen particularly with reference to Fig. 3.

At either end of said segment Idil i an arcuate insulated segment iii. As the gear 42 rotates with pintle 22, the contact IE8 engages either metallic segment It!) or insulated arcuate segment l I l depending upon the position of the door 29, and by adjustment of the respective lengths of said metallic and insulated segments I09 and III, the amount of swing of door 26 may be varied.

When the contact I08 engages insulated segment I I I, the ground connection is broken. Thereupon current through coil i 82 is broken and the contact between contacts S64 is broken, thereby de-energizing the solenoid 11 and allowing the door to close by action of springs 28 and 29. Similarly it will be seen that if the switch 81 is manually closed, and assuming that the thermal switch 8! is closed, coil i It of relay H1 is closed, closing contacts H8 and energizing solenoid 16 which opens the door in the opposite direction. Similarly a holding circuit is established by reasonof energizing coil H6 and closing contacts H9 which, even after release of switch 81 establishes a circuit through coil H6 so long as contact E2I engages the metallic segment portion are on gear 32.

Immediately upon said contact I2! engaging insulated segment ill, coil lie is tie-energized and breaks contacts H9 and de-energizcs solenoid 16 and closes door 29.

If two persons should approach door so from opposite directions at or about the same time, both switche cc and 81 are closed and accordingly both solenoids 16 and 11 are energized. Therefore, the two cylinders t5 and 46 are in equilibrium and since equal force is applied in opposite directions to each of racks 43, door 20 remains stationary. It will be apparent from Fig. 4 that this condition will produce overheating of the coils of sole- ,noids 1G and 11 unless the circuit is broken, but if this condition should exist, then the thermal jswitches 8| will break and the relays I02 and I06 will return to normal position. However, if one person manually opens door 29 until one of contacts IE8 or IZI is removed from contact with segment I69, by reason of rotation of gear 42, then one or the other of the relays IM or II1 will be tie-energized and the circuits restored to normal. It will be seen that the relative lengths of segments I99, III and MI is such that either contact I08 or contact I2I is always in contact.

An alternative construction is shown diagrammatically in Fig. 9. Pintle 222 of door 220 bears gear 223 which engages rack 224. It will be observed that there is only one rack 224. Back 224 is directly connected by rod 226 to horizontally reciprocating piston 221 in cylinder 228. Piston 221 and cylinder 228 are similar in construction to piston t1 and cylinder 46. Left-hand port 23I of cylinder 228 is connected through valve 232 to a source of compressed air, said valve 232 being controlled by solenoid 233. The right-hand 236 port of cylinder 228 is connected through valve 231 to a source of compressed air and said valve is controlled by solenoid 233. Switches 24! and 242, one pole of each of which is connected to one secondary pole 2M of transformer 2&2, are provided on opposite sides of door 2%.

Upon closing of switch 2H current flows from pole 24! of transformer 2E2 through said switch Ni thence to contact 243 of relay 24s. Since relay 244 is normally biased upward, contact is then established with contact 256 and thence through coil 24'. of relay 2A3 which causes establishment of contact between contacts 2st and 25L Thereupon current flows from the primary side of transformer through the relay 258 and to contact 252 on relay 253 which is normally biased upward, thence across to contact 254 and through coil 256 of relay 251 and thence back to transformer 262. Relays 2 3 i and 2:33 are arranged to latch in upper position until released, as hereinafter appears. Energization of coil 256 causes relay 251 to establish contact between contacts 258 and 259 which thereupon establishes a primary circuit through solenoid 238 which actuates valve 231 and causes piston 221 and rack 224 to move to the left as viewed in Fig. 9 and door 228 to swing to the right. When cam 26! on rack 22c contacts switch 262 it establishes a circuit from the secondary side of the transformer through the coil 263 of the latch control of relay 244 and this releases relay 244 and allows it to return to normal posi ion and accordingly breaks the contact through solenoid 238 and restores the piston 221 to normal position.

If, on the other hand, switch 2%. on door 226 is closed, relay 244 is energized and latched by reason of closing of contacts 266 and 261 of relay 2'41 and-establishment of a current through coil 263 of relay 245 which closes contacts 218 and 219 of said relay 244 and this in turn energizes -coil 269 in relay 253 which closes contacts 21! cam 21%; on rack 224 contacts switch 21s it establishes a circuit through the secondary side which energizes unlatching coil 216 in relay 248, thus permitting relay 2% to return to normal position. This results in lie-energizing solenoid 233 and closes door 220. 1

The position of cams 226i and 213 is made adjustable to govern the swing of the door.

If persons should close switches 24! and 242 simultaneously, coils 24'! and 263 would both be energized. However, the latches of relays 2M and M8 are so arranged that only one can be latched at a time and the one latched continues in that condition until unlatching switch 252 or 27 1 is closed, which occurs only upon full opening of door 229 in one direction or the other. Thus door 22% opens fully in the proper direction depending upon which switch is actuated first.

Although the present invention has been described in some detail by way of illustration and example, it is understood that certain changes and modifications may he made within the spirit of the invention and scope of the appended claims.

I claim:

1. In combination, a door in a doorway, a pintle, said door being arranged to swing about said pintle from closed to open position, a door check biasing said door toward closed position, a gear train comprising a gear on said pintle and a slidabie rack meshing with said gear arranged to swing said door to open position, fiuid means connected. to rack, valve means controlling said fiuid means to control movement of said rack, a solenoid controlling said valve means, a relay controlling energization of said solenoid, a switch, said switch being operable to energize said relay to open said door, an electrical contact and an insulated portion fixed for movement with said gear train, a sliding contact adjacent said electrical contact and said insulated portion, and holding means in said relay arranged to continue energization of said solenoid, said sliding contact being arranged to de energize said solenoid upon said door swinging through a predetermined angle such that said sliding contact breaks contact with said electrica1 contact and engages said insulated portion.

2. The combination of claim 1 which also comprises means mechanically actuated by said door to disengage said holding means.

3. In combination, a door in a doorway, a pintle, said door being arranged to swing about said pintle from closed position to an open position on either side of said doorwa a door check connected to said pintle biasing said door toward ciosed position, a gear on said pintle, a slidable rack meshing with said gear arranged to swing said door into either open position, fiuid means connected to said rack, valve means controlling said fluid means to control movement of said rack in either direction, a first and a second solenoid controlling said valve means, a first and a second relay controlling energization of said solenoids, a first and a second switch located on opposite sides of said door and supported thereon each manually actuated upon physical contact, one switch energizing said first relay and the other said switch energizing said second relay, an arcuate electrical contact fixed to said gear, insulated zones on said gear at either end of said arcuate electrical contact, a first and a second sliding contact adjacent said gear, holding means in each of said relays arranged to continue energization of said solenoids, said sliding contacts being arranged to de-energize said holding means upon said door swinging through a predetermined angle such that said sliding con-- tacts break contact with arcuate electrical contact and enter one of said insulated zones.

i. In combination, a door in a doorway, a pintle, said door being arranged to swing about said pintle from closed to open position, a door check connected to said pintle biasing said door toward closed position, a gear on said pintle, a linearly slidable rack meshing with said gear arranged to swing said door to open position, pneumatic means connected to said rack, valve means controlling said pneumatic means to control movement of said rack, a solenoid controlling said valve means, a relay controlling energizetion of said solenoid, a switch on said door and manually actuated upon physical contact, said switch energizing said relay to open said door, an ornate electrical contact fixed to said gear, an insulated zone on said gear, a sliding contact adjacent said gear, and holding means in said relay arranged to continue energization of said solenoid said sliding contact being arranged to (lo-energize said solenoid upon said door swinging t rough a predetermined angle such that said sliding contact breaks contact with said arcuate electrical contact and enters said insulated zone.

5. In combination with a door supported hingedly within a doorway for swingable movement to open position to either side of doorway, driving means for opening said door in either direction, a first electrical means arranged upon energization to actuate said driving means appropriate to cause said door to normally swing open to one side of said doorway through a pro-deterined angle, second electrical means arranged upon energization to actuate said driving means appropriate to cause said door to normally swing open to the other side of said doorway through a pre-determined angle, a first switch on one side of said door energizing said first electrical means, a second switch on. the opposite side of said door for energizing said second electrical means, a

first holding relay in circuit in said first electrical means arranged to continue energization of said first electric means, a second holding relay in circuit in said second electric means to continue energization of said second electrical means, said first and second electrical means and said driving means being balanced to hold said door in equilibrium when said first contact switch is actuated and said second contact switch is actuated before said door has swung through said predetermined angle, and a tie-energizing switch arranged to ale-energize first and second holding relays after said door been swung through said predetermined angle in either direction.

6. In combination, a door in a doorway, a pintle, said door being arranged to swing about said pintle from closed position to an open position on either side of said doorway, means biasing said door to closed position, a gear train rotating said pintle, said gear train comprising a pinion on said pintle and a reciprocable rack arranged to swing said door to open position on either side of said doorway, fiuid means connected to said rack, valve means controlling said fluid means to control movement of said rack in either direction, a first and a second solenoid controlling said valve means, a first and a second relay controlling energization of said solenoids, a first and a second switch located on opposite sides of said door, one said switch energizing said first relay and the other said switch energizing said second relay, an electrical contact portion and an insulated portion at each end of said electrical contact portion, said electrical contact portion and said insulated portion all being movable with one of the elements of said gear train, a first and a second sliding contact positioned adjacent said electrical contact portion and said insulated portions, holding means in each of said relays arranged to maintain energization of said solenoids, said sliding contacts being arranged to de-energize said holding means upon said door swinging through a predetermined angle such that said sliding contacts breakcontact with said electrical contact portion and engage one of said insulated portions.

7. The combination of claim 6, in which said holding means are arranged to continue energization of both said solenoids after one of said switches has been actuated and the other of said switches has been actuated before said door has swung through said predetermined angle whereby said fluid means is maintained in equilibrium thereby maintaining said door stationary until said door is manually swung through said predetermined angle.

8. In combination, a door in a doorway, a pintle on said door, said door being arranged to swing about said pintle from closed position to an open position on either side of said door- Way, a door check connected to said pintle biasing said door toward closed position, a gear on said pintle, a slidable rack meshing with said gear arranged to swing said door into either open position, fluid means connected to said rack, valve means controlling said fluid means to control movement of said rack in either direction,

a first and a second solenoid controlling said valve means, a first and a second relay controlling energization of said solenoids, a first and a second switch located on opposite sides of said door and supported thereon each manually actuated upon physical contact, one said switch energizing said first relay and the other said switch energizing said second relay, holding means in each of said relays arranged to continue energization of said solenoids until said door has swung through a predetermined angle, a third switch at one end of the linear movement of said rack, and a fourth switch at the opposite end of the linear movement of said rack, said third and fourth switches being arranged to de-energize said holding means upon said door swinging through said predetermined angle such that said rack contacts said third or said fourth switch.

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